These are very complex questions and the answers are not as simple as looking at your favorite veggies. In the image above you can see a handheld brix refractometer. These are not very expensive and they are used to find sugar content or brix, in brews, honey, fruit, and virtually any liquid. You are probably thinking, how does a sugar content relate to a healthy plant?
As you know photosynthesis is the plants mechanism for converting sunlight into carbohydrates or sugars, so high sugar content means the plant is highly effective at photosynthesis, i.e. healthy. Production of sugars means the leaves are healthy, but that sugar energy needs to be stored within the plant to ensure the plant can survive in adverse weather or drought.
Using a refractometer is easy enough anyone can do it. Since water naturally has no sugar it can be used to calibrate the device. On the tip of the tool is a blue area with a piece of clear plastic covering it. Lift the plastic and squeeze a drop of fluid from the plant onto the blue area. Cover with the plastic cover, and look through the blunt end while pointing it toward the sun. You will see a line appear which corresponds to the sugar content. You will then need to locate or download a brixing chart for the plant you tested since some plants are naturally sweeter than others.
Dr. Thomas Dykstra is a well-known expert in the field of agriculture and pest control. He has conducted extensive research on the relationship between Brix levels and plant health. He explains that higher brix levels are associated with stronger immune systems.
Dr. Dykstra has found that many pests prefer plants with lower Brix levels. This is because these plants are generally less healthy and more susceptible to attack. In the Regenerative Agriculture podcast he stated that Insects can only see and feed on unhealthy plants.
When we consider the methods commonly used to irradicate pest pressure, which inevitably lead to unhealthy soil, which leads to unhealthy plants, we can see how good intentions can lead make the problem worse.
